Finding the Fourth Proportional to 2,620.78, 3,617.45 and 1,559.30

Step by Step Solution

1. Step 1: Write the proportion equation
   2,620.78 : 3,617.45 = 1,559.30 : x
2. Step 2: Convert to fraction form
   2,620.78/3,617.45 = 1,559.30/x
3. Step 3: Cross multiply
   2,620.78x = 3,617.45 × 1,559.30
4. Step 4: Simplify right side
   2,620.78x = 5,640,689.79
5. Step 5: Solve for x
   x = 5,640,689.79/2,620.78
6. Step 6: Final answer
   x = 2,152.29